Solving the problem of heat leaks by means of window slots can be insulated. This approach makes it possible to reduce energy consumption by fifteen percent. In addition to the sealing of cracks, it will also be useful to install an additional glass that will create an air gap, which acts as a heat insulator. Of course, it is more advisable to install modern plastic windows. To increase the effectiveness of the method, the window between the balcony and the room also needs to be replaced.